Field of the Invention
The present invention pertains generally to power masonry tools and related devices for cutting and grinding. More specifically, the present invention relates to power saws of the “cutoff” type and systems that further maximize containment of dust contaminant while cutting cinder block, concrete, brick, clay, stone, tile and the like.
Description of the Prior Art
Power saws of the “cut-off” variety have been known for some time that employ a rotating circular blade applied to a stationary workpiece, such as wood, masonry or stone materials. An early version of a radial saw was invented by Raymond De Walt in 1922. These types of saws further include what is known as a “chop saw” which may be used for cutting lengths of pipe, steel, and other masonry objects. The chop saw comprises a 111otor coupled to a circular blade (or grinding wheel) pivotally supported for manual arcuate movement relative to a supporting surface such as a worktable.
An example of systems and methods comprising a chop saw are disclosed in U.S. Pat. No. 7,543,522 entitled “Adjustable Fence Assembly for Chop Saw,” to Chen. Some additional features known for chop saws include compounding the blade to change its angle with respect to the horizontal plane; or a sliding compound feature so that the blade can make larger cuts relative to a circular blade diameter. Some chop saws further employ a laser guide such as the configuration disclosed in U.S. Pat. No. 4,257,297 entitled “Circular Saw with Visual Cut Line Indicator,” to Nidbella.
Also known, is a problem of uncontrolled release of and exposure to airborne dust and particulate matter resulting from cutting a workpiece. Accordingly, government agencies such as OSHA have promulgated safety and health requirements for wet and dry cutting. The California Occupational Safety and Health Act of 1973 requires employers to provide a safe and healthful work place and gives CallOSHA regulatory jurisdiction over all public and private employers in California. Henceforth, employers must be compliant with all regulations set forth in Title 8 of The California Code of Regulations. In addition to health issues, the dust by-products present a clean-up challenge, even if all individuals in a contained environment have donned respirators.
Development of wet cutting devices and methods is one solution to dust abatement. In doing so, water is applied at a blade cutting edge where dust is entrained to a fluid and directed to a holding area. While most wet cutting methods work relatively well, they create additional problems of waste water pollution and environmental concerns. Further, the slurry created will adhere to cutting tool materials and components that also require periodic cleaning.
Many prior art solutions have been proposed that specifically employ dry means to control dust. Examples of such designs include, “Cutting And Dust Collecting Assembly,” by Johansson, U. S. Pat. App. Pub. No. 2008/0163492, “Cutting Apparatus with Dust Discharging,” to Kodani et al., U.S. Pat. No. 7,223,161, “Dust-Free Masonry Cutting Tool,” to Bath, U.S. Pat. No. 6,595,196, “Dust Collector for A Power Tool,” by Miller et al., U. S. Pat. Pub. No. 2007/0017191, to name a few. Such solutions generally may be suitable for their general purposes however none of these solutions are applicable for a chop saw. Yet another similar device was proposed by one of the present inventors, Guth entitled “Dust Collection System for A Masonry Saw,” U.S. Pat. No. 7,013,884, and assigned to Masonry Technology Incorporated. This dust abatement design is applicable to a masonry chop saw; however this design is not easily portable and requires a separate hook up to a vacuum system.
In light of the above, it is an object of the present invention to provide a Chop Saw with Dust Collection that is highly portable and lighter in weight as compared prior art solutions. More specifically, it is an object of the present invention to provide a masonry chop saw that integrates dust collection to a single portable unit. It is still a further object of the present invention to provide a dry dust collection design that is easily cleaned. It is still further an object of the present invention to provide a design that includes a variety of innovative features over prior designs.